Fix NULL lifecycle state in CSV import in 'IMPORT' mode

When import mode IMPORT is turned when importing a CSV and a lifecycle state is mentioned in it, the lifecycle state is not set (NULL) when the documents are created.

How to reproduce:

• fire up a 9.10 Nuxeo instance with addon nuxeo-csv and all the HFs
• create a CSV file in your workstation with the following content:

  name,type,dc:title,ecm:currentLifeCycleState
  "file1","File","File 1","approved"
  

• log in the Web UI and navigate to a workspace
• click on the Add Content button
• goto to the CSV tab in the create popup
• select the CSV file created earlier, turn on the Apply Date, Author and Dublin Core properties. switch and click on the CREATE button to launch the import

Expected result: a File document is created with lifecycle state approved
Actual result: a File document is created with lifecycle state set to NULL